JP2003253245A - Light-shielding agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-shielding agent effectively shielding unnecessary light radiated from an image-displaying apparatus in a front face member for the image-displaying apparatus, and having excellent solubility in an organic solvent, light resistance and environmental resistance, and to provide its application. <P>SOLUTION: The light-shielding agent contains a cyanine dye having an anion of a benzenedithiol metal complex as a counter ion. The front face member for the image-displaying apparatus uses the cyanine dye. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light-shielding agent containing a cyanine dye, and more particularly to a light-shielding agent containing a cyanine dye having an anion of a benzenedithiol metal complex as a counter ion.

[0002]

2. Description of the Related Art With the start of high-definition television broadcasting, the demand for plasma display type television receivers is rapidly increasing. A plasma display is an image display device that uses the plasma discharge light of a gas. It has a color purity comparable to that of a cathode ray tube, is easy to achieve full color, and has a wide viewing angle, so it is compatible with high-definition television broadcasting. It is being developed and mass-produced as a large image display device. However, Hiraki Uchiike, "Journal of the Institute of Image Information and Television Engineers", 51st
As reported in Volume 4, Issue 4, 459-463 (1997) and Shohei Nozaki's "Monthly Display", Volume 6, Issue 72-77 (2000).
In principle, the plasma display cannot avoid the emission of so-called "neon orange" and unnecessary near infrared radiation around a wavelength of 600 nm, which is emitted when excited neon atoms return to the ground state. However, when mixed with red light emission, there is a problem that vivid red display with good color purity cannot be obtained, or the infrared remote controller malfunctions.

In order to solve this problem, a method of attaching a front member using a near-infrared absorbing agent to a display portion of a plasma display has been conventionally proposed. For example, Japanese Patent Laid-Open No. 9-241520 discloses a near-infrared absorbing material. A front member using a nickel complex-based, azo-based, or anthraquinone-based organic dye compound as an agent is also disclosed in JP-A-10-1288.
Japanese Unexamined Patent Publication No. 98 proposes a front member using a heterocyclic, anthraquinone, or dithiol nickel complex organic dye compound.

However, since many of these organic dye compounds have low solubility in organic solvents, they interfere with the work of dissolving them in organic solvents and applying them to the transparent base material of the front member made of synthetic resin or the like. However, since the light resistance to ambient light such as natural light and artificial light is not sufficient, there has been a problem that the light-shielding ability of the front member is likely to deteriorate when used for a long period of time.

[0005]

In view of such a situation, the present invention effectively blocks unnecessary light radiated from a video display device in a front member for a video display device, and dissolves it in an organic solvent. Another object of the present invention is to provide a light-shielding agent having excellent light resistance and environment resistance and its use.

[0006]

[Means for Solving the Problems]
A search revealed that a cyanine dye with the anion of the benzenedithiol metal complex as a counterion has an absorption maximum in the visible to infrared region, and when used as a front member attached to an image display device such as a plasma display, It has been found to effectively block the unwanted light emitted. Further, it has been found that such a cyanine dye is excellent in solubility in an organic solvent, light resistance, and environment resistance, and that even when used for a long period of time, it is possible to efficiently manufacture a front member for a video device whose light-shielding ability is difficult to be reduced. .

That is, the present invention solves the above problems by providing a light-shielding agent containing a cyanine dye having the anion of the benzenedithiol metal complex represented by the general formula 1 as a counter ion.

[0008]

[Chemical 5] (In the general formula 1, X represents a metal atom.)

Further, the present invention solves the above-mentioned problems by providing a front member for a video display device using a cyanine dye having a counter ion of an anion of a benzenedithiol metal complex represented by the general formula 1. .

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, the present invention provides a light-shielding agent containing a cyanine dye having an anion of a benzenedithiol metal complex represented by the general formula 1 as a counter ion,
The present invention relates to a front member for a video display device, which uses such a cyanine dye.

[0011]

[Chemical 6]

In the general formula 1, X represents a metal atom,
Usually, it is selected from transition metals of Groups 3 to 12 of the Periodic Table, and among them, in terms of manufacturing cost, Group 9 to Group 11 of the Periodic Table, for example, cobalt, nickel, Copper or the like is preferable. In general formula 1,
The position at which the morpholinosulfonyl group is bonded to the benzene ring may be the ortho position or the meta position with respect to the thio group, but the meta position is preferred from the viewpoint of production cost.

Examples of the cation in the cyanine dye represented by the general formula 1 include those represented by the general formula 2.

[0014]

[Chemical 7]

In the general formula 2, Y is a monomethine chain,
Alternatively, a plurality of methine groups are bonded to each other, for example, a polymethine chain such as a dimethine chain, a trimethine chain, a tetramethine chain, a pentamethine chain, a hexamethine chain, or a heptamethine chain. Then, a monomethine chain, a trimethine chain, a pentamethine chain and a heptamethine chain are preferable.

Such a methine chain may form a cyclic structure, and each cyclic structure has a double bond and / or one or more heteroatoms, for example, a cyclobutene ring, a cyclopentene ring, a cyclohexene ring, Benzene ring, dehydrodecalin ring, pyridine ring, dihydropyridine ring, tetrahydropyridine ring, furan ring, dihydrofuran ring, thiophene ring, dihydrothiophene ring, hexahydroquinoline ring and the like monocyclic or condensed polycyclic ring .

The methine chain and cyclic structure may have one or more substituents without departing from the object of the present invention. Examples of the substituent in the methine chain and the cyclic structure include, for example, methyl group, ethyl group, vinyl group, propyl group, isopropyl group, isopropenyl group, 1-propenyl group, 2-propenyl group, 2-propynyl group, butyl group, Isobutyl group, sec-butyl group, tert-butyl group, 1,3-butadienyl group, 2-butenyl group, pentyl group, isopentyl group, neopentyl group, tert-
Short-chain long aliphatic hydrocarbon groups such as pentyl group, 2-pentenyl group, 2-pentene-4-ynyl group, methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, sec-butoxy group, tert- Ether group such as butoxy group, pentyloxy group, phenoxy group, anilino group, o-triidino group, m-triidino group, p-triidino group, xylidino group, amino group such as diphenylamino group, fluoro group, chloro group, etc. Examples thereof include a halogen group and a hydroxy group.

The general formula Z ¹ and Z ² in the 2 represent the same or different aromatic or heterocyclic ring together, these aromatic rings and heterocyclic ring may have one or more substituents. Z ¹
Examples of the aromatic ring for Z ² and Z ² include a benzene ring, naphthalene ring, azulene ring, anthracene ring, phenanthrene ring, and biphenyl ring, and examples of the heterocycle include a nitrogen atom, a phosphorus atom, an oxygen atom, and sulfur. Atom, selenium atom, tellurium atom or the like, which contains one or more heteroatoms of Group 15 or Group 16 in the periodic table, for example, imidazoline ring, imidazole ring, benzimidazole ring, α-naphthoimidazole ring, β -Naphthoimidazole ring, indole ring, isoindole ring,
Indolenine ring, isoindolenine ring, benzoindolenine ring, pyridinoindolenine ring, oxazoline ring, oxazole ring, isoxazole ring, benzoxazole ring, pyridinoxazole ring, α-naphthoxoxazole ring, β-naphthoxoxazole ring , Selenazoline ring, selenazole ring, benzoselenazole ring, α-naphthoselenazole ring, β-naphthoselenazole ring, thiazoline ring, thiazole ring, isothiazole ring, benzothiazole ring, α-naphthothiazole ring, β-naphthothiazole ring Ring, tellurazoline ring, tellurazole ring, benzoterrazole ring, α-naphthoterrazole ring, β-naphthoterrazole ring, further acridine ring, anthracene ring,
Isoquinoline ring, isopyrrole ring, imidanoxaline ring, indandione ring, indazole ring, indaline ring, oxadiazole ring, carbazole ring, xanthene ring, quinazoline ring, quinoxaline ring, quinoline ring, chroman ring, cyclohexanedione ring, cyclopentanedione ring , Cinnoline ring, thiodiazole ring, thiooxazolidone ring, thiophene ring, thionaphthene ring, thiobarbituric acid ring, thiohydantoin ring, tetrazole ring, triazine ring, naphthyridine ring, piperazine ring, pyrazine ring, pyrazole ring, pyrazoline ring, pyrazolidine ring , Pyrazolone ring, pyran ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrylium ring, pyrrolidine ring, pyrroline ring, pyrrole ring, phenazine ring, phenanthridine ring,
Phenanthroline ring, phthalazine ring, pteridine ring, furazane ring, furan ring, purine ring, benzoxazine ring,
Examples thereof include a benzopyran ring, a morpholine ring and a rhodanine ring.

The substituents in Z ¹ and Z ² include, for example, methyl group, ethyl group, vinyl group, propyl group, isopropyl group, isopropenyl group, 1-propenyl group,
2-propenyl group, 2-propynyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, 2
-Butenyl group, 1,3-butadienyl group, pentyl group,
Isopentyl group, neopentyl group, tert-pentyl group, 1-methylpentyl group, 2-methylpentyl group, 2
-Pentenyl group, 2-pentene-4-ynyl group, hexyl group, isohexyl group, 5-methylhexyl group, heptyl group, octyl group, nonyl group, decyl group, aliphatic hydrocarbon group such as dodecyl group, cyclopropyl group A cycloaliphatic hydrocarbon group such as cyclobutyl group, cyclopentyl group, cyclohexyl group and cyclohexenyl group, phenyl group, o-
Tolyl group, m-tolyl group, p-tolyl group, xylyl group,
Aromatic hydrocarbon groups such as mesityl group, o-cumenyl group, m-cumenyl group, p-cumenyl group, biphenylyl group, methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, sec-butoxy group. Group, ether group such as tert-butoxy group, pentyloxy group, phenoxy group, methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, butoxycarbonyl group, acetyl group, ester group such as benzoyloxy group, methylamino group, dimethyl group Amino group, ethylamino group, diethylamino group, propylamino group, dipropylamino group, isopropylamino group, diisopropylamino group, butylamino group, dibutylamino group, isobutylamino group, diisobutylamino group, sec-butylamino group, te t-butylamino group, pentylamino group, dipentylamino group, anilino group, o-triidino group, m-toluidino group, p-toluidino group, xylidino group, diphenylamino group and other amino groups, quinolyl group, piperidino group, Heterocyclic groups such as pyridyl groups and morpholino groups, halogen groups such as fluoro groups, chloro groups, bromo groups and iodo groups, hydroxy groups, carboxy groups, cyano groups, nitro groups, and substituents formed by combining these groups Can be mentioned.

Specific examples of the cyanine dye used in the present invention include those represented by the chemical formulas 1 to 19. All of these have an absorption maximum in the visible to near-infrared region with a wavelength longer than 400 nm, preferably 550 to 900 nm, and have a molecular absorption coefficient at the absorption maximum wavelength (hereinafter, the molecular absorption coefficient at the absorption maximum wavelength is Abbreviated as “ε”) is 5 × 10 ⁴ or more, usually,
Since it is as large as 1 × 10 ⁵ or more, for example, when it is used as a front member attached to an image display device such as a plasma display, it does not impair the color purity of the three primary colors of an image, for example, “neon orange” light emission or near infrared rays. Since it effectively blocks unnecessary light radiated from image display devices, such as, it is possible to obtain high-quality images with excellent contrast and color reproducibility, and the infrared remote control may malfunction due to near infrared rays. Nor. In addition, since these cyanine dyes have high solubility in various kinds of organic solvents, particularly, ketone-based, halogenated hydrocarbon-based, ether-based, and ester-based organic solvents, they can be dissolved in an organic solvent to form a front member. In addition to facilitating the work of applying it to the transparent base material, which is the main body, and having great light resistance and environmental resistance to ambient light such as natural light and artificial light, the light-shielding ability of the front member is diminished even after long-term use. There are difficult characteristics.

[0021]

[Chemical 8]

[0022]

[Chemical 9]

[0023]

[Chemical 10]

[0024]

[Chemical 11]

[0025]

[Chemical 12]

[0026]

[Chemical 13]

[0027]

[Chemical 14]

[0028]

[Chemical 15]

[0029]

[Chemical 16]

[0030]

[Chemical 17]

[0031]

[Chemical 18]

[0032]

[Chemical 19]

[0033]

[Chemical 20]

[0034]

[Chemical 21]

[0035]

[Chemical formula 22]

[0036]

[Chemical formula 23]

[0037]

[Chemical formula 24]

[0038]

[Chemical 25]

[0039]

[Chemical formula 26]

Although such a cyanine dye can be prepared by various methods, if economic efficiency is important, a cyanine dye having an anion other than the anion of the benzenedithiol metal complex as a counter ion and a benzenedithiol metal complex are usually used. A method of subjecting to a general ion exchange reaction is suitable. The cyanine dyes represented by Chemical Formulas 1 to 19 can be obtained in desired amounts by this method. Both the cyanine dye and the benzenedithiol metal complex to be subjected to the ion exchange reaction can be prepared by known methods or can be prepared according to known methods. You can use it after doing so.

Now, the front member for an image display device of the present invention using such a cyanine dye will be described. The front member of the present invention comprises at least a transparent base material as a main component of the front member and a general formula as a light-shielding agent. And a cyanine dye having an anion of the benzenedithiol metal complex as a counter ion. Incidentally, the "light-shielding agent" referred to in the present invention, by using for such a front member, unnecessary light emitted from the image display device, in particular,
A light-absorbing organic compound or a composition containing a light-absorbing organic compound that substantially blocks light in the visible to near-infrared region is meant.

As the transparent substrate, in the entire visible region,
Light transmittance of 50% or more, preferably 70% or more, for example, ABS resin, polyacrylic acid resin, polyacrylic acid ester resin, polyarylate resin, polyester resin, polyether sulfone resin, polyvinyl chloride resin,
Examples thereof include polyolefin resins, polycarbonate resins, polyvinyl acetate resins, polystyrene resins, polymethacrylic acid resins, polymethacrylic acid ester resins, and further glass, ceramics, etc. These may be used in appropriate combination as necessary. Among these, in terms of light transmittance and mechanical strength, polyacrylic acid resin, polyacrylic acid ester resin, polyarylate resin, polyester resin, polyether sulfone resin, polyolefin resin, polycarbonate resin, polymethacrylic acid resin, Polymethacrylic acid ester resins are particularly preferred.

The front member for an image display device of the present invention is used in an image display device after a cyanine dye represented by the general formula 1 and having an anion of a benzenedithiol metal complex as a counter ion is mixed with such a transparent substrate. Depending on the shape of the display part, for example, a transparent base that has been formed into a film shape, a sheet shape, a panel shape, or a film shape, a sheet shape, a panel shape, etc. according to the shape of the display part. A light-shielding layer made of a cyanine dye represented by the general formula 1 and having an anion of a benzenedithiol metal complex as a counterion is formed by adhering it to one side or both sides of the material. Although the thickness of the transparent base material depends on the material of the transparent base material and the area of the display portion of the video display device, it is usually 0.
It is 5 mm or more, preferably 1 mm or more, while in terms of weight, it is usually 10 mm or less, preferably 5 mm or less. Depending on the image display device, instead of directly attaching the transparent base material to the display unit, the transparent base material is once attached to a glass plate or the like according to the shape of the display unit, and the glass plate is attached to the display unit of the image display device. May be installed. In such a case, the transparent substrate is formed to have a relatively thin thickness, for example, in the form of a film or a sheet, and an adhesive layer or the like for sticking the transparent substrate to a glass plate is formed on one surface thereof.

In the former method of mixing the cyanine dye into the transparent substrate, for example, the transparent substrate and the cyanine dye are melt-kneaded and, if necessary, once formed into pellets, and then extrusion molding or injection molding. By a method such as press molding, molding is performed according to the shape of the display portion in the video display device, or the raw material monomer of the transparent substrate and the cyanine dye are mixed and cast-polymerized according to the shape of the display portion. .

On the other hand, in the latter method in which a cyanine dye layer is provided in close contact with a transparent substrate, for example, a binder is allowed to coexist, and the cyanine dye is mixed with, for example, chloroform, cyclohexanone or ethyl methyl ketone. The shape of the display part in the video display device after being dissolved or dispersed in an appropriate organic solvent such as a ketone type such as isopropyl methyl ketone, a halogenated hydrocarbon type, an ether type such as ethylene glycol monopropyl ether, and an ester type. Depending on, for example, a film,
Direct coating on one or both sides of a transparent substrate that has been molded into a sheet or panel, or a solution or dispersion prepared in the same way to a film or sheet of the same material as in the transparent substrate. After once applied, the film or sheet is attached to one side or both sides of the transparent substrate that has been formed according to the shape of the display section.

As the binder, for example, ethylene-
Vinyl acetate copolymer resin, ethylene-vinyl alcohol copolymer resin, cellulose acetate resin, vinyl acetate resin, cellulose resin, nylon, phenol resin, phenoxy resin, polyester resin, polyethylmethacrylate resin, polycarbonate resin, polystyrene resin, Polysulfone resin, polyvinyl butyral resin, polymethylmethacrylate resin and the like can be mentioned. If necessary,
These are used in appropriate combination. Such a binder is usually 10 to 1,000 times, preferably 50 to 50 times by weight ratio with respect to the cyanine dye of the present invention.
Used 0 times. When the cyanine dye is applied as a dispersion liquid, a solid cyanine dye is used with a particle size of 0.1 to 10
The particles are dispersed in the form of fine particles of μm, preferably 0.5 to 5 μm.

To apply a solution or dispersion containing a cyanine dye to a transparent substrate, etc., it is widely used in the art.
For example, a dipping method, a flow coating method, a spraying method, a bar coating method, a gravure coating method, a roll coating method, a blade coating method, an air knife coating method or the like is applied, and these are appropriately combined and applied. .

The light-shielding agent of the present invention is widely used in the art, together with a cyanine dye represented by the general formula 1 and having a counterion of the anion of a benzenedithiol metal complex, as long as it does not deviate from the object of the present invention. , Aminium salt compounds, amino compounds, aminothiol nickel complex compounds, anthraquinone compounds, immonium compounds, cyanine compounds, diimonium compounds, dithiol nickel complex compounds, triallylmethane compounds, naphthoquinone compounds, nitroso compounds And its metal salts, phthalocyanine compounds, carbon black,
Near infrared absorbers containing indium tin oxide, antimony tin oxide, etc., benzotriazole compounds, benzophenone compounds, hydroxybenzoate compounds, titanium oxide, zinc oxide, cerium oxide, iron oxide, barium sulfate and other ultraviolet absorbers, Is an antioxidant, flame retardant, stabilizer, lubricant, antistatic agent, heat anti-aging agent,
It may contain one or more release agents. The cyanine dye of the present invention, when used in combination with a near-infrared absorbing agent or an ultraviolet absorbing agent as described above, markedly improves the light resistance of the organic coloring matter compounds contained in these, and they can be exposed to ambient light such as natural light and artificial light. Effectively suppresses fading, denaturation and decomposition. The cyanine dye of the present invention that blocks near-infrared rays can be advantageously used as a near-infrared absorber or near-infrared ray blocking agent alone or in combination with other compounds that absorb near-infrared rays.

Further, the front member for an image display device of the present invention is generally used in the art together with the cyanine dye represented by the general formula 1 and having the anion of the benzenedithiol metal complex as a counter ion, if necessary. For example, silver, silver-palladium alloy, indium oxide, indium oxide-
Electromagnetic wave shielding agent containing tin oxide mixture (ITO), zinc oxide, etc., antireflection agent containing metal oxide, metal fluoride, metal silicide, metal boride, metal carbide, metal nitride, metal sulfide, etc. It does not prevent the combined use of one or more of the above. These materials are usually, for example, vacuum vapor deposition,
Is it formed by a method such as a sputtering method, an ion plating method, an ion beam assist method or the like on the transparent substrate as a layer independent of the light-shielding layer of the cyanine dye,
Alternatively, one or more of an ultraviolet ray blocking layer, an electromagnetic wave blocking layer, an antireflection layer, etc. are formed on a film or sheet of the same material as that of the transparent substrate, and the film or sheet is attached to the transparent substrate.

Further, the front member for an image display device of the present invention comprises a non-glare layer for suppressing the glare of the front member and widening the viewing angle, and a hard coat layer for protecting the surface of the front member, if necessary. The provision of one or a plurality of adhesive layers or the like for attaching the front member to a video display device, a glass plate or the like is not hindered.

The front member of the present invention thus obtained is
In the cyanine dye represented by the general formula 1 and having the anion of the benzenedithiol metal complex as a counter ion, as the cation cyanine dye, one having an appropriate absorption region according to the wavelength of light to be blocked should be selected. This makes it possible to selectively use unnecessary light in the visible to near-infrared region radiated from image display devices, particularly the "neon orange" emission or near-infrared light emitted from the image display device, without impairing the color purity of the three primary colors of the image. Shut off,
High-quality images with excellent contrast and color reproducibility can be obtained, and the infrared remote controller does not malfunction due to near infrared rays. Video display devices to which the front member of the present invention can be applied include, for example, direct-view TVs using cathode ray tubes, light-emitting panel TVs using plasma displays, electroluminescent displays, and non-light-emitting panel systems using liquid crystal displays. Examples include TVs and rear-projection TVs with built-in LCD projectors. Among these, the front member of the present invention is, in principle, applied to a light-emitting panel type TV that uses a plasma display or an electroluminescence display that easily emits unnecessary light including "neon orange" light emission. It can be applied very advantageously.

Embodiments of the present invention will be described below based on examples.

[0053]

[Example 1] <Shading agent> Acetonitrile 25 was placed in a reaction vessel.
Take 1.0 ml of cyanine dye 1.0
g was added and dissolved by heating. Separately, take 50 ml of acetonitrile in a container, add 1.3 g of a benzenedithiol copper complex represented by Chemical Formula 21 (trade name “EST5-Cu”, manufactured by Sumitomo Seika Chemicals Ltd.), heat and dissolve, and then put in a reaction container. In addition, the mixture was reacted at 60 ° C for 1 hour. When the solvent was distilled off from the reaction mixture and recrystallization was carried out with ethanol, 1.4 g of purple-brown crystals of the cyanine dye of the present invention represented by the chemical formula 1 was obtained.

[0054]

[Chemical 27]

[0055]

[Chemical 28]

When a part of the crystal was taken and the melting point was measured by a conventional method, the cyanine dye of this example had no melting point and was found to be 27
Decomposed at 2 ° C. In addition, when the visible absorption spectrum in a methanol solution was measured, the cyanine dye of this example had an absorption maximum near a wavelength of 588 nm, and the molecular extinction coefficient at the absorption maximum wavelength was 1.1 × 10 ⁵ .

The light-shielding agent containing such a cyanine dye is extremely useful for a front member for image display devices such as plasma displays.

[0058]

Example 2 <Shading agent> Acetonitrile 25 in a reaction vessel
Cyanine dye 1.0 represented by Formula 22
After adding g, it was heated and dissolved. Separately, take 50 ml of acetonitrile in a container, add 1.21 g of benzenedithiol copper complex represented by Chemical Formula 21 (trade name "EST5-Cu", manufactured by Sumitomo Seika Chemicals Co., Ltd.), heat and dissolve, and then put in a reaction container. In addition, the mixture was reacted at 60 ° C for 1 hour. The solvent was distilled off from the reaction mixture, and the mixture was recrystallized from a mixed solution of methanol / ethanol (volume ratio 1: 1).
The cyan crystals of the cyanine dye of the present invention represented by
g was obtained.

[0059]

[Chemical 29]

A part of the crystal was taken and the melting point was measured by a conventional method. As a result, the cyanine dye of this example had no melting point.
Decomposed at 0 ° C. In addition, when the visible absorption spectrum in a methanol solution was measured, the cyanine dye of this example had an absorption maximum near a wavelength of 575 nm, and the molecular extinction coefficient at the absorption maximum wavelength was 1.3 × 10 ⁵ .

The light-shielding agent containing such a cyanine dye is extremely useful for a front member for image display devices such as plasma displays.

[0062]

Example 3 <Light-shielding agent> 125 ml of an acetonitrile / chloroform mixture (volume ratio 3: 1) was placed in a reaction vessel, 5 g of a cyanine dye represented by the chemical formula 23 was added, and the mixture was heated and dissolved. Separately, 88 ml of acetonitrile / chloroform mixed solution (volume ratio 1: 1) is placed in a container, and the benzenedithiol nickel complex represented by the chemical formula 24 (trade name "EST
5-Ni ”, manufactured by Sumitomo Seika Chemicals Co., Ltd.), 4.86 g was taken and dissolved by heating. After the solvent was distilled off from the reaction mixture and the product was crystallized with methanol, 6.8 g of the cyanine dye of the present invention represented by the chemical formula 11 was obtained as green crystals.

[0063]

[Chemical 30]

[0064]

[Chemical 31]

When a part of the crystal was taken and the melting point was measured by a conventional method, the cyanine dye of this example had no melting point and was found to be 23
Decomposed at 0 ° C. In addition, when the visible absorption spectrum in a methanol solution was measured, the cyanine dye of this example had an absorption maximum near a wavelength of 813 nm, and the molecular extinction coefficient at the absorption maximum wavelength was 2.5 × 10 ⁵ .

The light-shielding agent containing such a cyanine dye is extremely useful for a front member for image display devices such as plasma displays.

[0067]

Example 4 <Shading agent> 150 ml of an acetonitrile / chloroform mixed solution (volume ratio 5: 1) was placed in a reaction vessel, 5 g of a cyanine dye represented by the chemical formula 25 was added, and the mixture was heated and dissolved. Separately, take 150 ml of acetonitrile in a container, and use a benzenedithiol copper complex represented by chemical formula 21 (trade name "EST5-Cu", manufactured by Sumitomo Seika Co., Ltd.).
After taking 4.46 g and dissolving it by heating, it was added to the reaction vessel and reacted at 60 ° C. for 1 hour. After distilling off the solvent from the reaction mixture, a methanol / ethanol mixed liquid (volume ratio 1:
When crystallized with 1) and methanol, 6 g of a light green crystal of the cyanine dye of the present invention represented by the chemical formula 12 was obtained.

[0068]

[Chemical 32]

A part of the crystal was taken and the melting point was measured by a conventional method. The cyanine dye of this example had no melting point.
Decomposed at 8 ° C. In addition, when the visible absorption spectrum in a methanol solution was measured, the cyanine dye of this example had an absorption maximum near a wavelength of 845 nm, and the molecular extinction coefficient at the absorption maximum wavelength was 3.0 × 10 ⁵ .

The light-shielding agent containing such a cyanine dye is extremely useful for a front member for an image display device such as a plasma display.

[0071]

Example 5 <Light-shielding agent> 125 ml of an acetonitrile / chloroform mixed solution (volume ratio 4: 1) was placed in a reaction vessel, 5 g of a cyanine dye represented by the chemical formula 25 was added, and the mixture was heated and dissolved. Separately, 88 ml of acetonitrile / chloroform mixed solution (volume ratio 1: 1) is placed in a container, and the benzenedithiol nickel complex represented by the chemical formula 24 (trade name "EST
5-Ni ”, manufactured by Sumitomo Seika Co., Ltd.) 4.4 g,
After being heated and dissolved, it was added to the reaction vessel and reacted at 60 ° C. for 1 hour. When the solvent was distilled off from the reaction mixture and the product was crystallized with methanol, 6.1 g of a deep green crystal of the cyanine dye of the present invention represented by the chemical formula 13 was obtained.

When a part of the crystal was taken and the melting point was measured by a conventional method, the cyanine dye of this example had no melting point, and
Decomposed at 0 ° C. In addition, when the visible absorption spectrum in a methanol solution was measured, the cyanine dye of this example had an absorption maximum near a wavelength of 845 nm, and the molecular extinction coefficient at the absorption maximum wavelength was 3.0 × 10 ⁵ .

The light-shielding agent containing such a cyanine dye is extremely useful for a front member for image display devices such as plasma displays.

The cyanine dye used in the present invention is
Although there are some differences in charging conditions and yields depending on the structures, for example, those represented by Chemical Formulas 1 to 19 are all prepared by the method of Examples 1 to 5, or The desired amount can be obtained according to the method.

[0075]

Example 6 <Solubility of Cyanine Dye> The cyanine dyes of the present invention represented by the chemical formulas 3 and 4 at 20 ° C. in cyclohexanone, ethyl methyl ketone, chloroform or ethylene glycol monopropyl ether were prepared according to a conventional method. The solubility was checked. In parallel,
The solubility of the control cyanine dyes represented by Chemical Formulas 22 and 26 was examined in the same manner. The results are shown in Table 1. In Table 1, "++", "+", "±",
"-" And "---" are "easy-melting", "melting",
It is meant to be "substantially soluble", "poorly soluble" and "insoluble".

[0076]

[Chemical 33]

[0077]

[Table 1]

As shown in the results of Table 1, the chemical formula 22
And the control cyanine dye represented by the chemical formula 26 were both “substantially soluble” to “insoluble” in all organic solvents except chloroform, while those represented by the chemical formulas 3 and 4 were All of the cyanine dyes of the invention are "generally soluble" in all organic solvents used in the test.
It showed a significantly high solubility, which was judged to be “easy dissolution”. In particular, the solubility improvement in the ketone-based solvent cyclohexanone, ethyl methyl ketone, and the ether-based solvent ethylene glycol monopropyl ether was remarkable, whereas the control cyanine dyes were all "insoluble". All of the cyanine dyes of the present invention represented by Chemical Formula 3 and Chemical Formula 4 exhibited solubility that was judged to be "substantially soluble" for practical use or higher.

Comprehensively judging from the results shown in Table 1, the solubility of the cyanine dye in an organic solvent, particularly the solubility in a ketone or ether organic solvent, is obtained by employing the anion of the benzenedithiol metal complex as a counter ion. As a result, by using such a cyanine dye as a light-shielding agent, it is easy to dissolve the light-shielding agent in an organic solvent and apply it to a transparent substrate when manufacturing a front member for image display devices. Becomes

[0080]

Example 7 <Light resistance of cyanine dye> To 100 parts by weight of ethyl methyl ketone, a polymethacrylic acid ester-acrylic acid copolymer resin (trade name "XPD-
2000 ", sold by Chugai Trading Co., Ltd., and 5 parts by weight of cyanine dyes or dye mixtures shown in Table 2 (molar ratio 1: 1).
1 part by weight of any of the above) was added and dissolved at room temperature with stirring, and then a thin film was formed on the acrylic plate by spin coating. Using a spectrophotometer, according to a conventional method, the light transmittance in the ultraviolet to infrared region of the acrylic plate provided with a light-shielding layer with a cyanine dye, and the absorbance at the absorption maximum wavelength of each cyanine dye, immediately, A xenon lamp (150 W) was installed at a position 10 cm away from the acrylic plate, and after irradiating with light for 1 hour, the absorbance of the acrylic plate was measured again at the same wavelength.
The absorbance immediately before irradiation of the xenon lamp thus obtained was 1
The percentage of the absorbance (dye residual ratio) immediately after irradiation of the xenon lamp for 1 hour was calculated as 00 and used as a measure of the light resistance of the cyanine dye. The results are shown in Table 2. Regarding the acrylic plate provided with the light-shielding layer of the cyanine dye of the present invention represented by the chemical formulas 1 and 13, respectively,
1 and 2 show light transmission curves in the ultraviolet to infrared region. In addition, in Table 2, when the cyanine dye as a test sample is a mixture, the dye residual rate of the cyanine dye used in combination with the cyanine dye of the present invention is shown.

[0081]

[Chemical 34]

[0082]

[Table 2]

As can be seen from the results in Table 2, when the xenon lamp was irradiated for 1 hour, the amount of the related compound was about 20 to 60.
% Decomposed, whereas chemical formula 1, chemical formula 2, chemical formula 1
Each of the cyanine dyes of the present invention represented by Formula 2 and Chemical Formula 13 exhibited a high dye residual rate of more than 90%. In addition, the results of FIGS. 1 and 2 show that the cyanine dye of the present invention emits light in the visible to near-infrared region, particularly at a wavelength of 550.
It shows that the light of from to 900 nm is selectively blocked. These results show that when the cyanine dye of the present invention is used for a front member attached to an image display device such as a plasma display, it is unnecessary to be radiated from the image display device including “neon orange” light emission and near infrared rays. It shows that the light-blocking ability lasts longer than that of cyanine dyes that effectively block such light and do not use the anion of the benzenedithiol metal complex as a counterion.

Further, as seen from the results of Table 2, in the system in which any of the cyanine dyes of the present invention represented by the chemical formula 2 or chemical formula 12 and any of the related compounds represented by the chemical formula 20 or the chemical formula 27 is combined, It was confirmed that a high dye residual ratio, which was not achieved by using the control analog alone, was found. This shows that the cyanine dye of the present invention effectively improves the light resistance of the organic dye compound when used in combination with the light absorber containing the organic dye compound.

[0085]

[Embodiment 8] <Environmental resistance of cyanine dye> For an acrylic plate on which a light-shielding layer of a cyanine dye was formed in the same manner as in Example 7, immediately before and immediately after leaving for 24 hours at a temperature of 60 ° C and a relative humidity of 90%. The respective absorbances were measured, and the percentage of the absorbance immediately after being left with respect to the absorbance immediately before being left (dye residual ratio) was measured and used as a standard for the environmental resistance of the cyanine dye. The results are shown in Table 3. In Table 3, when the cyanine dye as the test sample is a mixture, the residual dye ratio of the cyanine dye used in combination with the cyanine dye of the present invention is shown.

[0086]

[Table 3]

As can be seen from the results in Table 3, the temperature 60
When left at ℃ and relative humidity of 90% for 24 hours, the chemical formula is 20.
And related compounds represented by Chemical Formula 27 have a light-shielding ability of 10%.
The cyanine dyes of the present invention represented by Chemical Formula 1, Chemical Formula 2, Chemical Formula 12, and Chemical Formula 13 all showed a high residual dye ratio of more than 95%. These results indicate that the cyanine dye of the present invention has a high temperature,
When used as a front member attached to an image display device such as a plasma display, which has excellent environmental resistance to high humidity and is inevitable at high temperatures during operation, compared to a cyanine dye that does not use the anion of a benzenedithiol metal complex as a counter ion, It shows that the shading ability lasts longer.

[0088]

[Embodiment 9] <Front member for image display device> 100 parts by weight of a 20% by weight toluene solution of a saturated copolyester resin (trade name "Byron 200" manufactured by Toyobo Co., Ltd.), chemical formula 1, chemical formula 2, Formula 12 or Formula 13
After mixing with a 0.5 wt% cyclohexanone solution of the cyanine dye represented by, toluene was added to adjust the concentration of the polyester resin to 9 wt%. Then, using a bar coater, this solution was uniformly applied to one side of a polyethylene terephthalate film (trade name "T100E", manufactured by Diafoil Hoechst Co., Ltd., thickness 100 μm) and dried to form a coating having a thickness of 4 μm. Four types of front members with membranes were made.

Without deteriorating the color purity of the three primary colors of the image,
Each of the front members of this example that effectively blocks unnecessary light radiated from the image display device can be advantageously applied to an image display device such as a plasma display.

[0090]

[Example 10] <Front member for image display device> An indium-tin oxide alloy was laminated on the side of the front member manufactured by the method of Example 8 on which the light-shielding layer was formed by the cyanine dye, under an argon / oxygen mixed gas stream. . Furthermore, a non-glare layer-formed surface of a commercially available polymethylmethacrylate resin panel (trade name "MR-NG" manufactured by Mitsubishi Rayon Co., Ltd.) having a non-glare layer was attached to the surface opposite to the front member. Then, four types of front members for video display devices were obtained.

All of the front members of this example which effectively prevent unnecessary light radiated from the image display device without causing glare and impairing the color purity of the three primary colors of the image,
It can be advantageously applied to video display devices such as plasma displays.

[0092]

As described above, the cyanine dye used in the present invention has an absorption maximum in the visible to near-infrared region, and when used as a light-shielding agent for a front member attached to an image display device such as a plasma display, It effectively blocks unnecessary light radiated from the image display device without impairing the color purity of the three primary colors, resulting in high-quality images with excellent contrast and color reproducibility. It does not malfunction due to infrared rays. Further, since the cyanine dye used in the present invention is excellent in solubility in organic solvents, light resistance, and environment resistance, even when used for a long period of time, the light shielding ability of the front member for a video display device is not easily diminished. It can be produced. In addition, since the cyanine dye used in the present invention has the property of significantly improving the light resistance of the organic dye compound, when it is combined with another organic dye compound to form the light-shielding layer in the front member for an image display device. Therefore, it has a practical advantage that the amount of other organic dye compound used in combination is small.

It can be said that the present invention, which has such a remarkable effect, is a significant invention that contributes greatly to the field.

[Brief description of drawings]

FIG. 1 is a diagram showing the light transmittance of an acrylic plate provided with a light-shielding layer of the cyanine dye of the present invention.

FIG. 2 is a diagram showing the light transmittance of an acrylic plate provided with a light-shielding layer of another cyanine dye of the present invention.

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Claims (4)

[Claims] 1. A light-shielding agent comprising a cyanine dye having an anion of a benzenedithiol metal complex represented by the general formula 1 as a counter ion. [Chemical 1] (In the general formula 1, X represents a metal atom.) 2. The light-shielding agent according to claim 1, wherein the cation in the cyanine dye is represented by the general formula 2. [Chemical 2] (In the general formula 2, Y represents a methine chain, and the methine chain may have a substituent and / or a cyclic structure. Z
¹ and Z ² represent the same or different aromatic rings or heterocycles, and these aromatic rings and heterocycles may have a substituent. ) 3. A front member for a video display device, which uses a cyanine dye having an anion of a benzenedithiol metal complex represented by the general formula 1 as a counter ion. [Chemical 3] (In the general formula 1, X represents a metal atom.) 4. The front member for a video display device according to claim 3, wherein the cation in the cyanine dye is represented by the general formula 2. [Chemical 4] (In the general formula 2, Y represents a methine chain, and the methine chain may have a substituent and / or a cyclic structure. Z
¹ and Z ² represent the same or different aromatic rings or heterocycles, and these aromatic rings and heterocycles may have a substituent. )